A wireless access point (AP) is a wireless switch applicable to a wireless network and also a core of the wireless network. The wireless AP is an access point for a user terminal to access a wired network. A wireless AP is primarily used to access a wired network from a broadband home, in a building, or in a community, and its typical coverage distance is dozens to hundreds of meters. Currently based on technologies of 802.11 series, most wireless APs provide an access point client mode, and may have a wireless connection with other APs to extend network coverage.
The wireless fidelity (Wireless Fidelity, wi-fi) technology has been developed rapidly and applied widely in the past decade. The Wi-Fi technology is an Internet technology allows a user terminal to access an email, a webpage, and streaming media, and provides the user terminal with wireless broadband Internet access. Meanwhile, it is also a fast and convenient means of accessing the Internet at home, in an office or on a trip. A place where a Wi-Fi network can be accessed is called a hotspot. There are more and more scenarios where multiple Wi-Fi-enabled APs are combined, as shown in FIG. 1 and FIG. 2. In FIG. 1, an indoor user terminal is connected to the Internet by using an indoor AP. Equipped with a Wi-Fi search function, the indoor user terminal searches for and is connected to a service set identifier (SSID) name of the indoor AP, and enables the user terminal to be connected to the Internet by using the indoor AP. In FIG. 2, an outdoor user terminal is connected to the Internet by using a mobile AP. Equipped with a Wi-Fi search function, the outdoor user terminal searches for and is connected to an SSID name of the mobile AP, and causes the user terminal to be connected to a 3G network by using the mobile AP.
Currently, 3G dial-up-based Internet access manner of the user terminal is convenient and fast, and most user terminals support the function of the 3G dial-up access to the Internet. However, ongoing increase of user terminals may exhaust limited network resources. Therefore, disadvantage of the prior art is that numerous user terminals increase the frequency of using network resources and lead to network congestion.